Submission #1176334

#	Time	Username	Problem	Language	Result	Execution time	Memory
1176334		QuocSensei	Klasika (COCI20_klasika)	C++20	110 / 110	481 ms	337840 KiB

klasika

#include <bits/stdc++.h>

#define ll long long
#define el cout << '\n'
#define BIT(n) (1ll << n)
#define bit(mask, i) ((mask >> i) & 1)
#define ii pair<int, int>
#define fi first
#define se second

using namespace std;

const int maxn = 2e5;
const int maxbit = 30;
const int INF = 1e9;

struct Trie
{
    struct Node
    {
        int child[2];
        int minId;

        Node()
        {
            memset(child, -1, sizeof child);
            minId = INF;
        }
    };
    vector<Node> nodes;
    Trie()
    {
        nodes.push_back(Node());
    }
    void addNum(int u, int id)
    {
        int pos = 0;
        for (int i = maxbit; i >= 0; i--)
        {
            int e = bit(u, i);
            if (nodes[pos].child[e] == -1)
            {
                nodes.push_back(Node());
                nodes[pos].child[e] = nodes.size() - 1;
            }
            pos = nodes[pos].child[e];
            nodes[pos].minId = min(nodes[pos].minId, id);
        }
    }
    int getMaxXor(int u, int id)
    {
        int pos = 0, ans = 0;
        for (int i = maxbit; i >= 0; i--)
        {
            int needBit = bit(u, i) ^ 1;
            int c1 = nodes[pos].child[needBit];
            int c0 = nodes[pos].child[needBit ^ 1];

            if (c1 != -1 && nodes[c1].minId <= id)
            {
                ans |= BIT(i);
                pos = c1;
            }
            else pos = c0;
        }
        return ans;
    }
};

int q, ans[maxn + 10], dp[maxn + 10], n = 1, id[maxn + 10];
vector<ii> query[maxn + 10];
vector<int> adj[maxn + 10], v[maxn + 10];
Trie trie[maxn + 10];

void dfs(int top)
{
    v[top].push_back(top);
    trie[top].addNum(dp[top], id[top]);
    for (int next_top : adj[top])
    {
        dfs(next_top);
        if (v[top].size() < v[next_top].size())
        {
            swap(v[top], v[next_top]);
            swap(trie[top], trie[next_top]);
        }
        for (auto x : v[next_top])
        {
            v[top].push_back(x);
            trie[top].addNum(dp[x], id[x]);
        }
    }

    for (ii p : query[top])
    {
        int dist = p.fi;
        int idx = p.se;
        ans[idx] = trie[top].getMaxXor(dist, idx);
    }
}

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    if (fopen("KLASIKA.INP", "r"))
    {
        freopen("KLASIKA.INP", "r", stdin);
        freopen("KLASIKA.OUT", "w", stdout);
    }

    cin >> q;
    for (int i = 1; i <= q; i++)
    {
        string t;
        int a, b;
        cin >> t >> a >> b;
        if (t == "Add")
        {
            adj[a].push_back(++n);
            dp[n] = dp[a] ^ b;
            id[n] = i;
        }
        else
        {
            query[b].push_back({dp[a], i});
        }
    }
    memset(ans, -1, sizeof ans);
    dfs(1);
    for (int i = 1; i <= q; i++)
        if (ans[i] != -1)
            cout << ans[i], el;
}

Compilation message (stderr)

klasika.cpp: In function 'int main()':
klasika.cpp:107:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  107 |         freopen("KLASIKA.INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
klasika.cpp:108:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  108 |         freopen("KLASIKA.OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 22 / 22
• Subtask 3: 33 / 33
• Subtask 4: 44 / 44